"They've been talking about the gas tax for several years, and it goes nowhere," Branstad said.

The topic of the state's highway system and the gas tax consumed the largest slice of an hour-long town-hall meeting Thursday afternoon in Carroll, held at the Chamber of Commerce's Harold Bierl Meeting Room and attended by more than 50 people. Branstad, Iowa's four-term Republican governor, and Lt. Gov. Kim Reynolds led the event.

An Iowa House panel last year passed a measure to increase the fuel tax by 4 cents in 2013 and 4 cents in 2014 - acknowledging the wishes of Branstad who preferred to avoid a 2012 hike at the pumps. An Iowa Senate committee in 2012 had signed off on a 10-cent hike.

But the proposals ran headlong into political obstacles and stalled.

Iowa's fuel tax has been set at 21 cents a gallon since 1988 - although consumers looking to buy ethanol or E85 pay 19 cents a gallon.

The gas-tax increase, plus an increase in the tax for buying a new vehicle from 5 percent to 6 percent, would raise more than $200 million annually for Iowa's roads and bridges.

Branstad said Thursday the state is long overdue for a gas-tax increase. But the reality is the public judges gas taxes in their entirety, he said.

"With what's going on in Syria, it could be $4.59 a gallon," Branstad said. (According to Triple A, the average price of regular gas in Iowa early this morning stood at $3.62 a gallon.)

Branstad also took a shot at Big Oil, saying the industry is responsible for a large share of the cost to motorists at the pump - and that it resists renewable-energy products central to Iowa's economy.

"They're spending all their time and money attacking renewable fuels," Branstad said.

Branstad turned the gas tax-roads discussion back to the audience, asking what town-hall attendees would do to raise money to increase state Road Use Tax Fund coffers - which supply dollars for road-and-bridge work.

Branstad said the reality is that even a modest increase to the gas tax can have devastating consequences for many Iowans.

"There's a lot of low-income people that are just getting by," Branstad said.

That considered, Branstad said he wouldn't flat out refuse to sign a gas-tax increase if it passes the Legislature - as former Gov. Chet Culver, a Democrat, did.

Branstad suggested a combination package for raising revenue.

"We have to do something we can get both Democrats and Republicans to agree to," Branstad said.

In other issues at the town hall:

- Carroll County Supervisors Chairman Mark Beardmore, a Carroll Republican who had advocated an exemption for the county from the developing statewide mental-health system, pressed Branstad to explain the logic behind the Iowa Department of Human Service's rejection of a waiver for Carroll County.

Beardmore said Carroll County had strong marks as a stand-alone provider and had developed an enviable financial position. The county now will be forced into a region with some counties that have operated mental-health services in the red, Beardmore said.

Branstad said state officials had to make a decision on what would work for all 99 counties, and that most states in the nation have unified mental-health systems.

"I wished every other county in the State of Iowa had been run like Carroll County," Branstad said. "We wouldn't have to do this."

- Branstad said one of his goals in the next year is to use tax policy and other resources to make Iowa as attractive as possible for military veterans, as the United States winds down its involvement in Afghanistan.

- Carroll resident John Cook, an active Democrat, asked Branstad what the state is doing to reduce carbon emissions. Branstad did not challenge Cook's assertions on the role of global warming. The governor sounded support for a move to more electric and natural-gas vehicles and continued support for the renewable-fuels industry as a whole.

- Reynolds stressed the role of science and math education in Iowa, saying future jobs would rely on the success of such programs in Iowa's classrooms.

"Iowa is really poised for some significant growth," Reynolds said.

Carroll Mayor Adam Schweers, a Republican who received the governor's endorsement in an unsuccessful Statehouse bid in 2012, introduced Branstad and Reynolds. Schweers is serving as a co-chairman on the governor's re-election campaign.